Self-healing polyurethane elastomer with wider damping temperature range by synergistic interaction of suspended chains and dynamic disulfide bonds

In order to overcome the sharp damping peak that limits the application of polyurethane elastomers (PUE) and the cut that affects its service life as functional floor coating, a self-healing PUE with broader damping temperature range and high self-healing efficiency was prepared by incorporation of prepolymer synthesized from polycaprolactone diol and isophorone diisocyanate and chain extenders including 4,4′-diaminodiphenyl disulphide (DAPS) and double-hydroxyl suspended chains synthesized from IPDI, polyethylene glycol monomethyl ether and 2-amino-1,3-propanediol. The effects of different functionalities were carefully investigated at the fixed dosage of 30%. DAPS with dynamic disulfide bonds were revealed of higher efficiency in improving the damping properties and self-healing rate. The synergistic effects of the two functionalities were studied by varying the usage of DAPS from 10% to 50% when the suspension chain amount fixed at 30%. The effective damping (tan δ > 0.3) domain presents a range of 131.57 °C with 100% increase of tan δ compared with the base sample, and the self-healing efficiency reaches 95% when the usage of DAPS and suspension chain were 30% and 50%, respectively. The modified material achieved prominent improvement in damping properties and cut self-healing ability, showing potential application in aerospace and acoustic coatings for vibration and noise reduction.